That Perec quote in full

I got the detail slightly misremembered. The below section appears in a letter to the mother of a murdered woman, by the man who murdered her. She, hired as an au pair by the man, allowed for his son to drown, and his wife subsequently commited suicide. In this part of the letter, he is still searching for the au pair and is running out of options...

So then I began to appeal to the exhausting resources of the irrational. If your mysterious and beautiful American neighbour had still been there, you can be sure I would have had recourse to her disturbing services; instead, I went into turning tables, I wore rings encrusted with particular stones, I had magnets and hanged men's fingernails and tiny bottles of herbs, seeds, and coloured stones sewn into the hems of my clothes; I consulted wizards and water diviners, fortune tellers and crystal-bal gazers and soothsayers of all sorts; they threw dice, or burnt a photograph of your daughter in a white porcelain plate and examined the ash, they rubbed their left arms with fresh verbena leaves, put hyenas' gallstones under their tongues, spread flour on the floor, made unending anagrams of your daughter's names and pseudonyms, or replaced the letters of her name with figures in an attempt to reach 253, examined candle flames through vases filed with water, threw salt into fire and listened to the crackling...